Introduction Criminal justice systems, with their powerful enforcement procedures, entail sensitive fundamental rights considerations. Detention is a severe form of such procedural powers, and at times is needed during pre-trial procedures to ensure that criminal investigations are not undermined. Detention, both pre- and post-trial, can also be important for the protection of victims and public safety in general. As with all kinds of power, with detention comes a great responsibility to ensure that the measure is proportionate in terms of what it seeks to achieve in relation to the restrictions placed on the rights of suspects, accused or sentenced persons. In other words, there has to be a good balance between restrictions on personal liberty and the necessities of the criminal process, with due regard to the gravity of the crime in question. There are strong societal interests in finding such a balance: • Suspects and accused persons should as far as possible not be detained in line with the presumption of innocence.1 • Sentenced persons will eventually have to be reintegrated into society; the ‘social rehabilitation’ process needed for such reintegration, which should start from the very beginning of detention, is facilitated by reducing the detention period. • The costs of detention are generally much higher than alternatives to detention. • Mutual trust in each other’s justice systems among Member States is dependent on a sufficiently high ‘level’ or quality of the justice systems, including the conditions and application of detention. • A well-functioning European Union (EU) justice area based on trust, in turn, is needed to accommodate the increasingly cross-border nature of crime. The EU, while seeking to protect victims and the general public, has adopted a legal instrument promoting the reduction of pre-trial detention. It has also adopted a legal instrument on reducing detention post-trial. This post-trial instrument shares another overarching goal 1 The presumption of innocence is subject to EU legislation, with a Directive (pre-) adopted by the Council on 12 February 2016. The instrument does not deal with detention, other than making clear that pre-trial detention in itself does not violate the presumption of innocence. with a third instrument: social rehabilitation. These three instruments, adopted in 2008 and 2009, deal with transfers across EU-borders of 1) alternative measures to pre-trial detention, 2) alternative measures to posttrial detention as well as probation (conditional release), and 3) prison sentences. The main purpose of these three Framework Decisions is arguably to avoid the need for, or facilitate, the social rehabilitation of suspects, accused or sentenced persons by permitting them to be ‘closer to home’. This could be achieved with alternatives to detention in pretrial as well as post-trial settings, by encouraging probation, or by having individuals serve their sentences in a country where they have habitual residence and other connections, such as family and friends – important elements for successful social rehabilitation. A Framework Decision is the equivalent of a Direc­ tive, used before the Lisbon Treaty entered into force in  2009 in the area of police and judicial cooperation in criminal justice matters. However, Framework Decisions did not have direct effect before they were implemented and were not enforceable through the  EU courts until December 2014, five years after the Lisbon Treaty entered into force. Framework Decisions had to be ‘implemented’ while Directives are ‘transposed’. The European Commission requested the EU Agency for Fundamental Rights (FRA) to undertake research assessing the fundamental rights implications of these three instruments. As a consequence, this FRA report explores fundamental rights implications in the practical application of the three Framework Decisions. Due regard is given to relevant standards and guidance from, in particular, the Council of Europe and the United Nations. Examples include the Council of Europe recommendations and resolutions relating to penitentiary questions2 as well as subsequent developments of ECHR standards by the European Court of Human Rights (ECtHR), but also United Nations standards and norms in crime prevention and criminal justice.3 2 3 Council of Europe (2014), Compendium of conventions, recommendations and resolutions relating to penitentiary questions, May 2014. UNODC (2006a). 17